CommunityP Vijayalakshmi MS Aravind Eye Hospital & Post-Graduate Institute of Ophthalmology 1 Anna...

This issue is generously supported by

Sight Savers International UK

International Eye Foundation USA

Bartiméus Holland

Hilton/Perkins Program ofPerkins School

for the Blind USA

Hilton/Perkins Program

demonstrated that a significant

proportion of children in blind

schools or special education

have conditions which may be

improved by surgery, specifi-

cally cataract and some cases of

corneal scarring. Identification

of these children, followed

by surgery in the hands of

an experienced ophthalmologist

and follow-up to manage errors

and amblyopia, is an important part of any

prevention of blindness programme. Dr

Vijay, in her article, gives information on

the management of surgically remediable

causes of childhood blindness. The role of

IOLs in the management of paediatric

cataract in developing countries is an

important area for evaluation.

Work from West and East Africa and

South America is reported in the very prac-

tical article by Lynne Ager which shows

that approximately half of all children in

blind schools can be helped to read normal

print (and therefore avoid the need of

Braille), if they are carefully refracted and

supplied with the appropriate spectacles

and magnifiers. This results in better educa-

tional opportunities and improved integra-

tion. A number of low vision programmes

in Africa and Asia for children in blind

schools and special education have now

CommunityEEyyee HHeeaalltthh

A N I N T E R N A T I O N A L J O U R N A L T O P R O M O T E E Y E H E A L T H W O R L D W I D E

Community

Allen Foster FRCS FRCOphthMedical Director

Christoffel Blindenmission

Senior Lecturer

International Centre for Eye Health

11–43 Bath Street

London EC1V 9EL, UK

There are an estimated 1.5 million blind

childrenworld-wide.Table1 documents

where they live and Table 2 gives the major

anatomical causes. The years of blindness

resulting from these diseases represent a

major social and economic burden on com-

munities, as well as individuals.

This issue specifically asks the question

‘How can blind children be helped?’ It con-

centrates on what can be done to help the

child with significant visual loss, rather

than what can be done to prevent blindness

in children, which has been discussed in

previous issues (see Issues 5, 8, 11, 22).

Dr Rahi discusses how to examine a child

who is reported to have visual problems in

order to assess the level of visual function,

the cause of visual loss and the prognosis

for future vision. The examination is often

difficult to perform, but it is important that

time is taken, if necessary over several

examinations, to determine accurately visu-

al function, aetiology and prognosis.

Surveys from around the world have

How Can BlindChildren Be Helped?

been implemented, with encouraging

results.

Blind schools are good places to start

such programmes as studies show that

5–10% of children can benefit by surgery

and 10–15% can have improved vision

with spectacles alone.

To conclude, blindness in children is

important because of the numbers affected

and the years of resulting disability. As

Visually impaired children, some with albinism, inKenya Photo: Clare Gilbert

How Can Blind Children Be Helped? Allen Foster 33

Children in Blind Schools P Vijayalakshmi 35

Examination of a Child with Visual Loss Jugnoo S Rahi 36

Optical Services for Visually Impaired

Lynne AgerChildren 38

The Role of Integrated Education for

M N G Mani 41Blind Children

Statistics: People and Eyes Ian Murdoch 43

The Global Initiative R B Porter 44

33

Eye Health No 27 /fonts 9/8/01 10:54 am Page 33

34 Community Eye Health Vol 11 No. 27 1 9 9 8

Commun it yEEyyee HHeeaalltthh

Volume 11 Issue No. 27 1998

International Centre for Eye HealthInstitute of OphthalmologyUniversity College London11- 43 Bath StreetLondon EClV 9EL

Tel: (+44)(0)171-608 6909/6910/6923Fax: (+44)(0)171-250 3207e-mail: [email protected]

Associated withMoorfields Eye Hospital

World Health Organization Collaborating Centre for Prevention of Blindness

EditorDr Murray McGavin

Nurse ConsultantMs Susan Stevens

Administrative DirectorMs Ann Naughton

Editorial SecretaryMs Anita Shah

Editorial CommitteeDr Allen FosterDr Clare GilbertProfessor Gordon JohnsonDr Darwin MinassianDr Ian MurdochDr Richard WormaldDr Ellen Schwartz

Language and CommunicationConsultant Professor Detlef Prozesky

Consulting EditorsDr Harjinder Chana (Mozambique)Dr Parul Desai (UK)Dr Virgilio Galvis (Colombia)Professor M Daud Khan (Pakistan)Professor Volker Klauss (Germany)Dr Susan Lewallen (Canada) Dr Donald McLaren (UK)Dr Angela Reidy (UK)Professor I S Roy (India)Professor Hugh Taylor (Australia)Dr Randolph Whitfield, Jr (Kenya)

Indian EditionAn Indian edition with a local supplement is published and distributed by DANPCB in Delhi.

Typeset byRegent Typesetting, London

Printed byThe Heyford Press Ltd.ISSN 0953-6833

E d i t o r i a l

well as preventive measures to avoid blind-

ness in children, there is much that can be

done surgically and optically to improve

the vision of a significant proportion of

children with visual loss (Table 3). It is

proposed that a minimal requirement for

the developing world is 1 unit specialising

in ‘visual loss in children’ for every 10

million population. Such a unit requires an

experienced ophthalmologist and opto-

metrist who are willing to work as a team

with educationalists to provide services

and long term follow-up.

✩ ✩ ✩

Commun it y EEyyee HHeeaalltthh

Supported by:

Sight Savers International (United Kingdom)

Christoffel Blindenmission (Germany) and

Christian Blind Mission International

Danish Assistance to the National Programme for

Control of Blindness in India (Denmark/India)

International Glaucoma Association (United Kingdom)

Table 1: Magnitude of Blindness in Children

Region No. children No. Prev. Total %million blind /1,000 blind children

Africa 253 330,000 1.2 24India 340 270,000 0.8 20 Rest of Asia 264 220,000 0.8 16 China 336 200,000 0.6 12 Middle East 238 190,000 0.8 14 Latin America 167 100,000 0.6 8Western Economies 168 50,000 0.3 4Eastern Europe 77 40,000 0.5 2Total 1,843 1,400,000 0.71 100%

Table 2: Causes of Blindness in Children

Site No. blind % Conditions

Retina 400,000 29 Retinal dystrophies and ROP*Cornea 300,000 21 VAD, measles, ON and TEM*Globe 200,000 14 Microphthalmos, colobomaLens 130,000 9 Cataract and aphakiaOther 130,000 9 Cortical blindness, amblyopiaOptic Nerve 120,000 9 Optic atrophy / hypoplasiaGlaucoma 70,000 5 Bupthalmos or glaucomaUvea 50,000 4 Aniridia and uveitisTotal 1,400,000 100%

*ROP: Retinopathy of PrematurityVAD: Vitamin A Deficiency

ON: Ophthalmia NeonatorumTEM: Traditional Eye Medicines

Table 3: Avoidable Causes of Childhood Blindness by Region

Region Corneal Scar Cataract ROP Total

Africa 100,000 30,000 <500 130,000India 90,000 30,000 <500 120,000Rest of Asia 60,000 30,000 2,000 92,000Middle East 25,000 10,000 <1,000 35,000China 15,000 35,000 <1,000 50,000Latin America 10,000 10,000 25,000 45,000Eastern Europe <1,000 10,000 5,000 16,000Western Economies <1,000 5,000 6,000 12,000Total (approximates) 300,000 160,000 40,000 500,000


P Vijayalakshmi MSAravind Eye Hospital & Post-Graduate

Institute of Ophthalmology

1 Anna Nagar

Madurai

India

During our team’s routine screening of

children in blind schools in Madurai,

we find a considerable number of children

every year who can benefit by being

given spectacles, simple magnifiers or by

surgery. This situation can be attributed to

the fact that many of these children were

not seen by an ophthalmologist before

admission to these schools.

Children who have vision better than

counting fingers (CF) should be investi-

gated thoroughly and this includes anterior

segment examination, refraction and fund

-oscopy. With the preliminary diagnosis in

hand, the examination of refraction should

be given more importance. It may be prac-

tically difficult but every effort should be

made to achieve the best corrected visual

acuity with appropriate glasses. Many

times we come across children with

high myopia, macular dystrophy,

congenital nystagmus, microphthalmos,

albinism, coloboma, cone dystrophies, and

sometimes even optic atrophies showing

significant improvement for both distance

and near vision or sometimes with near

vision alone. Apart from doing routine

refraction, steps should be taken to

ascertain the acceptance of simple low

visual aids.

Often these children show very good

improvement with telescopes. The im-

proved visual acuity (telescopic) could

even be 6/6. Near vision also can be

improved in the same way with simple

magnifiers. It needs a lot of motivation

from parents, teachers and the children to

use these devices later in childhood.

Reluctance is always experienced particu-

larly since most of these children are

trained in the use of Braille.

The children who show minimal

improvement or no improvement at all,

even with low visual aids, are often those

with uncorrected aphakia because of dense

stimulus deprivation amblyopia.

The most important and significant

pathology causing blindness which was

untreated has been congenital cataract. In

this category of children are those who

have had no treatment or had treatment but

were not followed up properly or ended up

with complications. Under the ‘Seeing

2000’ programme sponsored by the Inter-

national Eye Foundation, 245 children

admitted into blind schools in the city were

examined by us in 1998. The main objec-

tive was to identify children who could

benefit by surgery. Of the 245 children, 16

were found to be blind due to unoperated

cataracts in both eyes. Thirteen were un-

corrected aphakics. Among the unoperated

children with cataract, nine had surgery.

The remaining seven did not have surgery

mainly because of less motivation by their

parents. The minimum vision gained by

those who had surgery was CF and the

maximum vision was 6/60 (Table 1).

Among these, three had intraocular lens

(IOL) implants. Most children had only

cataract extraction, either extracapsular

cataract extraction (ECCE) or lensectomy,

depending on the nature of the cataract

(partially absorbed or calcified). Nystag-

mus was present in almost all cases. The

number of children showing improvement

post-operatively even at this late stage of

childhood is encouraging and justifies the

undertaking of surgery after proper investi-

gation. The visual improvement was less

when the child had associated micro-

cornea, microphthalmos or coloboma.

Among the 13 children who had already

had surgery but were uncorrected, only a

few showed visual improvement with

aphakic correction (Table 2). Only patient

no. 12 showed significant improvement

with a telescope. Others were either not

co-operative or unable to ‘fix’ because of

nystagmus. Most were densely amblyopic

and the visual acuity ranged from CF to

6/60. This strongly supports the fact that

bilateral childhood cataract in South

India is a significant cause of childhood

35Community Eye Health Vol 11 No. 27 1 9 9 8

Review article

Children in Blind Schools: What Conditions Should beT r e a t e d ?

Table 1: Children with Cataract Showing Visual Improvement

after Surgical Intervention

No. Age Surgical Procedure Pre-op. VA Post-op. VA

1 14 ECCE PL 2/602 14 ECCE PL 3/603 8 ECCE + IOL HM CF4 15 PCIOL HM 6/605 6 Lensectomy PL+ 1/606 6 Lensectomy PL+ 2/607 12 ECCE + IOL PL 1/608 9 Lensectomy PL 1/609 9 Lensectomy 1/60 3/60

Surgery for congenital cataractPhoto: Clare Gilbert

Table 2: Aphakic Children Showing Improvement with Correction

No. VA (without VA (aphakic with NV DV NV (handcorrection) correction) (telescope) magnifier)

1 1/60 1/60 - - -2 2/60 2/60 - - -3 2/60 2/60 - - -4 CF CF - - -5 CF CF - - -6 2/60 2/60 - - -7 1/60 5/60 - - -8 1/60 5/60 N5 - -9 1/60 3/60 - - -

10 4/60 4/60 N12 - N1011 CF CF - - -12 1/60 6/60 - 6/12 N1213 1/60 4/60 - - -

Eye Health No 27 /fonts 9/8/01 10:54 am 5

Jugnoo S Rahi MSc FRCOphthMedical Research Council

Clinical Training Fellow

Departments of Epidemiology and

Ophthalmology

Institute of Child Health /Great Ormond

Street Hospital NHS Trust

30 Guilford Street

London WC1N 1EH, UK

O phthalmic examination of a child

with visual loss aims to confirm the

impairment, establish the diagnosis, identi-

fy the treatment required and describe the

prognosis for the disorder(s) causing visual

loss. The examination by ophthalmic pro-

fessionals is an important component of the

broader assessment of visual function and

educational needs of the child, which form

the basis of the plan of management of that

child and her/his family. The benefits of

evaluation by a multi-disciplinary team,

comprising ophthalmic and paediatric pro-

fessionals together with educationalists and

psychologists, are recognised.1 Therefore,

where the necessary resources exist, visual

assessment teams are being increasingly

established.

The ophthalmic examination of a child is

essentially the same as that of an adult but

with the techniques adapted according to

the child’s age, personality, ability to

co-operate, and level of responsiveness.

Any other non-ophthalmic disorders the

child may have will also need be taken into

account. Thus, the precise content and

sequence of the components of the exami-

nation will vary from child to child. Most

children can be successfully examined

without anaesthesia or sedation, which

are generally only necessary on clinical

grounds.

Taking a History

It should be remembered that the mother of

the child is the person who knows the child

better than anyone, and if she suspects that

her child may not be seeing normally then

this should be taken very seriously. It is

usually possible to assess the overall

level of visual function through a detailed

history, taken from the parents, and

possibly from other relatives and teachers,

as well as from the child, if appropriate.

The interview also provides the first

opportunity to assess the parents’ response

and adaptation to their child’s visual

problems and to establish a relationship

between the family and the ophthalmic

team.

Information on the age at onset, duration

and level of visual loss should be sought.

The presence or absence of specific symp-

toms and signs should be determined: these

include eye-poking, photophobia, signifi-

cant worsening of vision in dim or very

bright light, or nystagmus. It is also impor-

tant to enquire about any family history of

ocular or systemic diseases. Questions

should be asked about the mother’s preg-

nancy, the birth, including gestation and

birth weight, and the neonatal period. It

should be established whether the child’s

general development is normal or whether

there are concerns about hearing, speech,

motor or learning abilities. Finally, as

appropriate, it may be necessary to ask

about specific aetiological agents, such as

drugs, infections, nutritional deficiencies

or trauma.

The Ophthalmic Examination

Observing the child

The clinical examination starts during

the history taking, through assessment of

the child’s visual alertness and behaviour:

for example, her reaction to changing

the lighting, or if someone unknown

approaches her. The child should also

be observed for any external ocular

blindness and accounts for 12% of admis-

sions to blind schools.

One more condition which could be

treated surgically is corneal opacity of late

onset due to acquired pathology such as

keratomalacia. Either keratoplasty or opti-

cal iridectomy before dense amblyopia

develops is worth trying.

Conclusion

To conclude, we would like to emphasize

that all the children who are likely to be

admitted into blind schools should be

thoroughly examined by an ophthalmo-

logist. The eye specialist should have a

background of working with children and a

knowledge of amblyopia and the use of

low visual aids. With this approach, and if

simple low visual aids are introduced early

in life, the quality of education and life can

be significantly improved.

References

1 Eckstein M, Vijayalakshmi P, Killedar M,

Gilbert C, Foster A. Aetiology of childhood

cataract in South India. Br J Ophthalmol 1996;

80: 628–32.

2 Rahi JS, Sripathi S, Gilbert CE, Foster A.

Childhood blindness in India: causes in 1318

blind school students in nine states. Eye 1995; 9:

545–50.

3 Jain IS, Pillai P, Gangwar DN, Gopal L, Dhir SP.

Congenital cataract: management and results.

J Pediatr Ophthalmol Strabismus 1983; 20:

243–6.

4 Droste PJ, Archer SM, Halveston EM. Measure-

ment of low vision in children and infants.

Ophthalmology 1991; 98: 1513–8.

5 Robb RM, Petersen RA. Outcome of treatment

for bilateral congenital cataracts. Ophthalmic

Surgery 1992; 23: 650–6.

✩ ✩ ✩

Blind Schools

Examination of a Child with Visual Loss

Matching test (Sheridan-Gardner) tomeasure visual acuity Photo: David Taylor

Review article

Microcorneas and corneal scarringPhoto: Murray McGavin

36 Community Eye Health Vol 11 No. 27 1998


abnormalities, such as ptosis or nystagmus,

as well as for other unusual features, such

as abnormal head shape.

Testing visual fixation and following

The ability to fix and follow an object

should be tested as well as whether fixation

is central, steady and maintained.2 This is

particularly important in young infants and

in older children with other disabilities

who are unable to co-operate with formal

tests of vision. However, it should be

remembered that fixation and following

require normal ocular motor responses and,

even when normal, cannot be interpreted as

indicating a particular level of vision.

Examining pupillary responses

Assessment of pupil size and their response

to a bright light can be difficult, especially

in infants, but should be carried out. Ab-

normal responses are important diagnostic

clues. For example, a relative afferent

pupillary defect indicates asymmetrical

anterior visual pathway disease and a para-

doxical pupillary response may suggest

retinal disease.

Assessing eye movements and

strabismus

The ocular motor system should be

assessed by examining the corneal light

reflexes, and by the cover-uncover test to

detect strabismus. The range of ocular

movements should also be tested, especial-

ly when a neurological disorder is sus-

pected. Eye movements can be tested to

ascertain whether the child can follow a

moving object (smooth pursuit system),

and whether they can refixate on an object

introduced into the field of vision (saccadic

eye movements). Children are naturally

interested in faces, and the examiner

can use her/his own face as the object of

interest.

Examining the anterior segment

Wherever possible the cornea, iris, lens,

anterior chamber and anterior vitreous

should be examined using a slit-lamp.

Young infants can be examined

in this way if held up to the slit

lamp in the prone ‘flying baby’

position or, alternatively, by

using a hand held slit-lamp. If

a slit-lamp is not available,

examination is possible using a

magnifying loupe and appro-

priate light source. The organi-

sation, symmetry and clarity of

the structures of the anterior

segment should be carefully

evaluated. The intraocular

pressure should be measured

when there are specific concerns, using

methods appropriate to the child’s age and

level of cooperation. Pulse-air tonometry,

if available, is generally more suitable for

infants and young children but in older

children, applanation tonometry is usually

possible.

Examining the posterior segment

Examination of the fundus can be difficult

and dilation of the pupils is essential. It is

very important to examine the fundus of all

children who have reduced vision, as loss

of vision may be due to life threatening

conditions, such as retinoblastoma. In

young infants examination can be made

easier if the child is held and fed by a

parent while being examined. For older

children it may be necessary to wrap the

child in a blanket, and have an assistant

hold the child’s head steady during the

examination, after explaining to the parents

that the examination is not painful in

any way. Wherever possible, direct and

indirect ophthalmoscopes should be used.

Indirect ophthalmoscopy, if possible using

a 28+ or 30+ dioptre lens, provides a good

view of the entire fundus whilst direct

ophthalmoscopy allows more detailed

examination of structures such as the optic

disc and fovea.2

Refraction

As part of their initial ophthalmic examina-

tion, all children should be assessed by

cycloplegic refraction for the

presence of a refractive error, as

this may be the cause of the

visual impairment, as well as

providing diagnostic clues.

Examining the family

Ophthalmic examination of the

parents, siblings and other

family members is important

whenever the disorder causing

visual loss is suspected to be

hereditary, even if there is no

previously established family

history.

Measuring Visual Functions

Measuring visual functions in children is

not straightforward. The visual system is

relatively immature at birth and develop-

ment, particularly rapid in the first year of

life, continues into late childhood.3 There-

fore, it can be difficult to predict final

visual outcome in infants and very young

children, including some of those with

apparently very poor vision.4 Acuity is the

most frequently measured visual function

but others, such as visual fields and bino-

cularity, may be particularly relevant to the

overall functional assessment of the child.

Acuity

Despite the development of methods

appropriate to different ages, measuring

acuity remains difficult in infants, pre-

school children and those with other dis-

abilities. In addition, many techniques

require special equipment and conditions,

making them unsuitable for some settings.

Whichever method is used to measure a

child’s vision, it is important to assess

vision corrected for any refractive errors,

and to assess the eyes separately as well as

together whenever possible.

The acuity of infants may be measured

using forced choice preferential looking

methods using Teller or Cardiff acuity

cards, and by electro-physiological tests of

visual evoked potentials. Both techniques

are time-consuming, require special equip-

ment and trained personnel, and are

costly. Until recently these methods were

generally only used in specialised paedia-

tric ophthalmology units.2 In co-operative

children, aged 18– 24 months, it is possible

to use picture optotype tests (such as Kays

pictures) at very short distances. Standard

optotype tests, such as the Snellen E chart,

can generally only be used in children aged

3 years or above. It is important that testing

is carried out at the appropriate distance,

and, if possible, using linear optotype

systems to ensure the effect of crowding is

not overlooked in children with amblyopia.

37Community Eye Health Vol 11 No. 27 1998

Examining a Child

Portable slit-lamp examination in ChilePhoto: Clare Gilbert

The ‘flying baby’ position for slit-lamp examination

Photo: David Taylor


Lynne Ager

BSc MSc MCOptomc/o International Centre for Eye Health

11–43 Bath Street

London EC1V 9EL, UK

A n estimated 1 in 250 children are

visually impaired as a result of eye

disease. Some of these children have nearly

normal vision, some are totally blind, but

the majority fall into a broad range between

these two points. Children are said to have

‘low vision’ or ‘partial sight’ when they

have: (a) a corrected visual acuity in the

better eye of <6/18 to ‘perception of light’

(or a visual field of less than 10 degrees);

and (b) the ability to use their residual

vision to orientate themselves or to perform

tasks.1 They are identified at eye clinics,

school screening programmes, community

based rehabilitation (CBR) programmes or

special schools for the visually impaired.

The education, employment prospects,

independence and quality of life of a child

with low vision can all be improved by

enhancing vision. Optical devices (specta-

cles, magnifiers and telescopes) play a key

role in achieving this. Studies carried out in

East Africa,2 South America3 and West

Africa4 indicate that approximately half of

children who have low vision show an

improvement in distance and/or near visual

acuity with the help of spectacles, a magni-

fier or both. The majority of magnifiers are

prescribed for children who have a visual

acuity in the better eye of <6/60 to 1/60.3,4

The Role of Optical Services in the

Management of Children with Low

Vision

The management of children with low

vision requires co-operation between the

child, his/her family and eye care educa-

tional and social personnel. There are five

stages in the management of children with

low vision (Fig. 1). Eye care personnel are

primarily involved in the assessment and

monitoring stages which include: visual

acuity measurement (distance and near);

eye examination, diagnosis and prognosis;

surgical and/or medical treatment; and the

provision of optical services.

Sight is a key source of stimulus during

a child’s development, and so children

with low vision should be motivated to

make the maximum use of their residual

vision. This can be done using both non-

optical and optical methods.

Enhancing Vision Using Non-Optical

Methods

• Move CLOSER, e.g., use an angled

reading desk

• Use COLOUR to show objects more

clearly

• Use CONTRAST, e.g., eat white rice off

a coloured plate

• Pay attention to LIGHTING, e.g., sit

near a window in class

• Make objects LARGER, e.g., write with

larger letters

• Use a LINE-GUIDE such as a ruler when

reading and writing.

With some younger children and those

unable to read, a matching test, involving

matching letters on the distance chart with

those on a card held at near, can be used.

Visual fields

Formal visual field testing is generally only

possible in older children. However, useful

information about significant visual field

defects, such as hemianopia, can be

obtained by testing visual fields using

simple confrontation methods.2

Binocular vision

Assessment of the level of binocular vision

is primarily important in children with

strabismus. However, it can be a useful test

in the assessment of a child suspected of

having serious loss, as the presence of

binocular vision implies good acuity in

each eye. There are various clinical stereo-

acuity tests, some of which can be used

with young children.3

The Child with Very Poor Vision

When assessing a child thought to have

very poor vision, methods which can detect

very basic levels of visual function should

be used. Examples include assessing

whether a child responds in any way to a

bright light; or if they respond to a visual

threat, such as waving a hand fast in front

of the face. In infants a useful test is the

spinning test. In this test the child is held at

arms length facing the examiner, who spins

the child round several times. If, after stop-

ping spinning, the eyes have prolonged

nystagmus, this suggests that the child has

very poor vision (or cerebellar disease).

All these tests need to be interpreted

cautiously, as a normal response depends

on motor function as well as visual func-

tion. If these tests of basic visual function

are abnormal, electro-diagnostic tests (such

as electro-retinograms or visual evoked

responses) can be used to confirm whether

an abnormality is present or not. If these

facilities are not available it is advisable to

say to the parents that you need to examine

the child again in a few months’ time,

when the tests can be repeated.

What to Tell the Parents of a Child

Thought to be Blind

It is advisable to be cautious about giving a

definite visual prognosis to parents of

young children who appear to be blind. As

it is difficult to predict the final visual out-

come in young children, 4 it is important to

avoid judging the child’s visual function

too early in life. Whilst it is essential that

parents are not given unrealistic expecta-

tions of their child’s future vision, it is

important to remember that some children

with serious ocular disorders and apparent-

ly very poor vision, can achieve better than

expected overall visual ability.

References

1 Royal College of Ophthalmologists and the

British Paediatric Association. Ophthalmic

services for children. Report of joint working

party. London: Royal College of Ophthalmo-

logists and the British Paediatric Association,

1994.

2 Day S. History, examination and further investi-

gation. In: Taylor D., ed. Paediatric Ophthalmo-

logy 2nd ed. London: Blackwell Science, 1997:

77– 92.

3 Chandna A. Natural history of the development

of visual acuity in infants. Eye 1991; 5: 20–6.

4 Day S. Normal and abnormal visual develop-

ment. In: Paediatric Ophthalmology, see 2

above: 13– 28.

✩ ✩ ✩


Examining a Child

Optical Services for VisuallyImpaired Children

Review Article

Accurate refraction and spectacle correction help many children with lowvision

Photo: Murray McGavin


Enhancing Vision Using Optical

Devices

Optical devices play a key role in enhanc-

ing vision and reducing visual disability in

children with low vision. They include:

standard prescription spectacles; optical

low vision devices for distance vision; and

optical low vision devices for near vision.

(a) Standard prescription spectacles: It is

important to ensure that children with low

vision are refracted and provided with any

spectacles they require. Work in West

Africa indicates that at least 30% of

children with low vision need spectacles.4

Refraction should always be carried out

before a magnification assessment.

(b) Optical low vision devices for distance

vision: Distance vision magnification

requires a telescopic lens system. Tele-

scopes are expensive and have limited

applications. It is often more practical for a

child to sit near the front of class to see the

backboard than to use a telscope.

(c) Optical low vision devices for near

vision: An optical low vision device for

near vision uses one or more lenses placed

between the eye and an object to alter the

retinal image size of the object. This makes

the object larger and easier to see. The

minimum dioptric power of a device used

in this way is +4.00D. These devices are

inexpensive and have a wide range of

applications. They play a vital role in

giving children with low vision access to

print and illustrations in standard text-

books.

Prescribing Magnifiers for Near

Vision

The power of magnifier prescribed for a

child is determined by the child’s visual

requirements, recorded near visual acuity

and measured working distance. They are

prescribed, starting with low power magni-

fiers and then progressing to higher

powers. The higher the power, the smaller

the area of visual field seen through the

magnifier. More words in a sentence can

be viewed through a +10D magnifier than

through a +20D magnifier. The power of

the magnifier prescribed should be the

maximum power which enables the child

to perform the task required, but not above

requirements so that maximum visual field

is maintained. Moving the eye closer to the

lens of a hand-held or stand magnifier also

increases the field of view. In West Africa

71% of magnifiers prescribed were low

power magnifiers (under +25D).4 These

were prescribed more frequently for those

with a visual acuity of 3/60 or better. High

power magnifiers (over +25D) were pre-

scribed in 29% of cases and were mainly

prescribed for those with a visual acuity of

less than 3/60.

To determine the appropriate type of

magnifier it is important to assess the

child’s personality, co-ordination, motiva-

tion and task aims. The same magnification

can be provided using different mounting

systems and working distances. Optical

devices for near vision include: hand-

held magnifiers (illuminated or non-

illuminated); stand magnifiers (illuminated

or non-illuminated); spectacle mounted

magnifiers (e.g., high plus spectacle

lenses, hyperocular lenses); and spectacle

mounted telescopic units. The most widely

available optical low vision devices for

near vision are non-illuminated hand-

held magnifiers, non-illuminated stand

magnifiers, and high plus spectacle

lenses. Advantages and disadvantages of

these three types of magnifier are indicated

in Table 1.

There are many benefits in providing

magnifiers to children with low vision. The

magnifiers encourage children to use their

low vision to the full, thereby increasing

visual stimulus and helping the children’s

development. The magnifiers promote

literacy by increasing access to printed

material for educational purposes and

private reading. It is also more cost effec-

tive to provide children with optical

devices enabling them to use standard

books than to provide large print books

which are expensive and heavy to carry.

There are some limitations in providing

magnifiers. Using a magnifier may make a

child’s visual disability more noticeable

causing the child to feel different from

other children. The human and financial

resources available to provide the magni-

fiers may be limited. The child needs to be

taught carefully how to use the magnifier

as the restricted field of view can prevent a

child from perceiving the overall pattern of

words or sentences on a page.

Supply of Magnifiers

Low power magnifiers can be made easily

using locally available materials. An


Optical Services

Aphakic spectacle corrections after con-genital cataract surgery for two Romanianchildren Photo: Clare Gilbert

Stage 1

DETECTION

Stage 2

IDENTIFICATION

Stage 3

ASSESSMENT

Stage 4

TRAINING

Stage 5

MONITORING

Child’s eye problem suspected by familyteacher or health worker.

Visual screening by eye health worker, teacher or CBRworker to determine whether child has normal vision (>6/18),

low vision (<6/18–PL and useful vision) or total blindness.

CLINICAL (Eye Care Personnel)Examination and diagnosis; Treatment; Refraction;

Prescription and provision of optical low vision devices.

EDUCATIONAL (Special Education Personnel)Educational needs; Reading material;Regular/Special

School; Provision of non-optical low vision devices.

FUNCTIONAL (Social Services Personnel)Visual orientation/mobility; Visual communication;

Use of vision in activities of daily life.

Training in maximum use of vision and how to uselow vision devices by parents, teachers and CBR workers.

Monitoring of changes in child’s visual ability by parents,clinical, educational and CBR personnel.

Fig.1: Stages in the Management of Children with Low Vision


optical workshop in Nairobi, Kenya

developed a design using mounts made

from plastic drain-pipe tubing. These

are now used world-wide as they are

inexpensive (approx. $6 each) and robust.

Hand-held and stand magnifiers can be

made in a range of powers from +8D to

+28D. Instructions for making these are

available from Christoffel Blindenmission,

Nibelungenstrasse 124, D-64625 Bens-

heim, Germany. Higher power magnifiers

can be imported from Combined Optical

Industries Limited (COIL), UK or Eschen-

bach, Germany. These are made from

lightweight, plastic aspheric lenses and

cost between $6 (low power hand-held

magnifier) and $34 (high power stand mag-

nifier). They range in power from +8D to

+76D.

Case Studies

In West Africa, 291 students with low

vision were identified at eye clinics, special

schools for the visually impaired, integra-

tion programmes and CBR programmes

during 1995/6. All received an initial

visual assessment including distance and

near visual acuity measure–

ment, refraction, magnification

assessment and a quantitative

measure of their level of func-

tional vision. The functional

vision tests included orienta-

tion, activities of daily life,

ability to recognise pictures and

reading speed. A follow-up

assessment was received by

139 students. At first assess-

ment (128/291) of the students

showed an increase in distance

or near visual acuity with an

optical device. Potential to read

normal print (N10 or better),

with or without the help of

spectacles and/or a magnifier,

was shown by 55% (159/291)

of students. Those who bene-

fited were provided with optical

devices and all the children

with low vision received non-

optical low vision devices and

educational support. At follow-

up assessment six months later,

63% (88/139) of students with

low vision showed a further

improvement in their distance

visual acuity, near visual acuity

and/or their functional vision. In special

schools for the visually impaired in Ghana,

46% of students with low vision showed an

improvement in reading and/or writing at

their follow-up assessment.

These figures indicate that correctly pre-

scribed optical devices can be of signifi-

cant benefit to the child with low vision

and, therefore, the provision of optical

services should be an integral part of any

low vision service

References

1 WHO. The management of low vision in

children. Proceedings of WHO/PBL consulta-

tion, Bangkok, July 1992. WHO, 1993.

2 Silver J, Gilbert C, Spoerer P, Foster A. Low

vision in East African blind school students:

need for optical low vision services. Br J

Ophthalmol, 1995; 79: 814– 20.

3 Ager L R. Identifying children with low vision

who benefit from magnifiers: a visual assess-

ment of children at schools for the blind in

Colombia and Ecuador. Unpublished MSc

Community Eye Health Dissertation, ICEH,

London, 1994.

4 Ager L R. Annual report of low vision services,

Ghana National Eye Care Programme, 1996

✩ ✩ ✩


Optical Services

Using a stand magnifier for near visionPhoto: Lynne Ager

Table 1 : Practical Differences Between Magnifiers

Hand-Held Magnifiers Stand Magnifiers High PlusSpectacle Lenses

Uses • reading • reading • reading • looking at pictures • looking at pictures • writing • writing • looking at pictures• identifying money • close range• inspecting small objects

Advantages • easy to carry around • has a fixed, stable • range of magnification• available from low to • working distance • both hands free • medium power • easy to use • readily available• inexpensive to make • available in low, medium,• can be used at any • or high power• position or angle

Disadvantages • difficult to keep • one hand occupied • exact reading distance • appropriate distance • not useful for writing • important• one hand occupied • bulky to carry around • heavy to wear• difficult to hold steady • need flat working surface

WERKGROEP TROPISCHE

OOGHEELKUNDE

Course on Tropical Ophthalmology

Utrecht, The Netherlands

21–22 January, 1999

A Course on Tropical Ophthalmology will be held for the 5th time in Utrecht, The Netherlands

The Course is given in English and provides anoverview of Tropical Ophthalmology. Lecturersfrom different countries will be present.

The Course is open for Ophthalmologists andDoctors interested in Tropical Ophthalmology.

For more information contact:

P Hardus, A Van Dalsumlaan 531 3584 HL Utrecht, The Netherlands.Tel:/Fax 00 31 30 25 16 579


Review Article

Dr M N G ManiPrincipal

Sri Ramakrishna Mission Vidyalaya

College of Education

Coimbatore – 641020

India

Why Integration?

Over the years, studies in child develop-

ment, sociology, and special education

have led enlightened educators to the con-

clusion that blind children grow, flourish,

and achieve greater self and social fulfil-

ment by being nurtured in the least restric-

tive environment. Through local education,

supported by well prepared specialists in

education of the blind, these children may

enjoy everyday common experiences

essential to the development of a keen

awareness of the realities of the world

around them. With proper technical assis-

tance, consultation given to regular class-

room teachers, and a broad educational

environment, blind children are able to

show their true worth; they are then more

readily accepted socially by their sighted

counterparts. Statistics reveal that not even

10% of blind children in most of the devel-

oping countries are receiving any kind of

education, and therefore, integrated educa-

tion is considered to be the only practical

approach. It is the economically viable,

psychologically superior, and socially

acceptable model to bring all those

unreached blind children into the main-

stream of education.

Objectives of Integration

The true objectives of integrated education

are to:

• Provide the same opportunities and edu-

cational experiences for blind children

as those provided for sighted children

• Allow blind children – and their fami-

lies, neighbours, and friends – to inter-

act socially in normal situations

• Change the typical public response to

blindness by demonstrating that blind

children are children first and blind

children next

• Provide a natural basis for adult life

experiences so that blind students may

take their proper places as contributing

members in all sectors of society.

Integrated education is not simply placing

a child in a regular classroom. The child

needs assistance. Blind children can easily

assimilate more than 80% of teaching and

experience in the regular classroom if they

are provided with the correct material in

the correct form at the correct time.

Therefore, development of the right edu-

cational environment will make integra-

tion of blind children a reality.

Factors Contributing to the Success of

Integration

The major means of attaining successful

integration are:

1 Provision of specialised teachers to

serve as resource persons, to prepare

special materials, as required, and to

provide special instruction in those skills

peculiar to blindness such as Braille

reading and writing, use of reader ser-

vices, auditory perceptual training and

orientation and mobility.

2 Provision of all appropriate educational

texts and selected aids and appliances. If

textbooks are not available in Braille,

substantial quantities of individually

transcribed Braille materials may be

required.

3 Provision of consultation for regular

classroom teachers, school administra-

tors, families, local health authorities

and the general public on matters deal-

ing with education of blind children,

specialised training techniques and

selection of appropriate materials.

4 Full use of local consultants, specialists

and volunteers with special skills or

those who are willing to be trained to

assist in specialised ways, such as

through reading services, or materials

preparation including Braille transcrip-

tion.

Curriculum in Integrated Schools

A curriculum for blind children is never

less than the curriculum for sighted

children; on the contrary it is more compre-

hensive. In addition, for every skill expec-

tation of the sighted child, blind children

must do more. Apart from academic sub-

jects, integration becomes effective when

the blind child is well trained in compen-

satory skills such as Braille reading meth-

ods, use of slate and stylus, use of audio

equipment, development of visual percep-

tual activities, speed and accuracy in the

use of the abacus, skills of daily living and

orientation and mobility. In order to enable

the blind child to follow the general

curriculum without any difficulty, the

resource teacher, in consultation with the

regular teacher, can make changes in the

presentation of materials, if necessary.

There are four principles involved in the

preparation of materials.

• Duplication is the most encouraged

method of materials preparation

• Modifications, in terms of content,

method of display, type of material used,

and the response expectation from the

child, are sometimes made

• Sometimes, there is no suitable way

to modify materials and therefore an

experience may have to be Substituted

so that it closely approximates that

presented to sighted counterparts

Reading Braille Photo: Clare Gilbert

Children and teachers at work! Photo: Lynne Ager

The Role of Integrated Educationfor Blind Children




Integrated Education

• Under unavoidable circumstances, a con-

cept or a lesson may have to be Omitted.

Selection of an Appropriate Model of

Integrated Education

In developing countries, awareness of inte-

grated education is found among organisa-

tions working for blind persons and

amongst professionals as well. There is a

common consensus that integrated educa-

tion should aim at normalising the life and

education of the blind child but opinions

vary to a great extent about how to realise

the goal of integration. A minimum of ten

models of integrated education are current-

ly observed in developing countries.

Resource models with residential facili-

ties are predominately found in many

integrated programmes in developing

countries but these are as costly as special

school settings. The itinerant model, com-

posite areas approach, and other contract

specific cost-effective models have to be

tried out to reach the currently unreached

blind children in rural areas. There are

claims and counter-claims about the

superiority of one model over the other.

In this professional debate on models,

the real impact of integrated education

should not be lost.

In deciding the cost-effective models of

integrated education, three factors have to

be considered.

• Number of blind children in a locality

• The nature of services required by blind

children

• Expertise needed by a special teacher

and general classroom teachers

More than 90% of blind children in

developing countries are from rural areas,

which are scattered. In a rural locality, it is

difficult to find the required number of

blind children for resource models. In

such circumstances, the only cost-effective

model would be an itinerant approach

where one resource teacher can attend to

the needs of more blind children in a

cluster with the assistance of general class-

room teachers. Research clearly indicates

that resource models are academically

superior to all other models of integration

but duplication of resource models for

mass implementation is not feasible.

Now inclusive education is increasing in

special education and general education

itself is sensitised to take care of the educa-

tional needs of blind children.

Blind children require different kinds as

well as different levels of service. Children

who are at the primary level will require

the direct assistance of a specialist teacher

whereas children at higher levels depend

more on regular classroom teachers

provided they are given the necessary

materials for learning in the regular class-

room. Therefore, selection of a model

depends upon the nature of services

needed by the blind children.

The success of integration also depends

upon the extent of assistance provided by

the general classroom teachers. In integra-

tion, the general classroom teacher and the

specialist teacher are ‘two sides of the

same coin’ and, therefore, the general

education system itself should equip the

regular classroom teachers in pre-service

programmes to cope with the needs of

disabled children in general and blind

children in particular. Hence, blind

children can be served effectively by a

good combination of specialists and

general classroom teachers.

Role of Special Schools

Special schools should change their role by

serving blind children who cannot benefit

by integration. Blind children with addi-

tional disabilities require special school

services and, therefore, special schools will

continue to provide services. In fact, they

can become resource centres in a locality to

promote the cause of integrated education.

Conclusion

In countries like India where the numbers

of blind children are staggering, integration

emerges as the only alternative to reach the

unreached. Services for blind children in

the country are more than 100 years old but

the coverage of blind children in education

is not even 10%. This scenario will change

with the speedy implementation of inte-

grated education. ❏

OCULAR INFECTION: Investigation and Treatment in Practice

Authors: D Seal, A Bron and J Hay

This really useful book comprehensively covers the field of ocular infec-

tions and is an important contribution to the prevention of blindness. Eight

chapters cover general topics such as pathogenisis of infection, ocular

immunology and pharmacology and epidemiology applicable to ocular

infection, together with specific infections of ocular tissues and systems.

Professor Philip Thomas writes on tropical ophthalmomycoses. Chapter

eight deals with hospital acquired infections, covering clinics, operating

theatres, surgical prophylaxis and eye banking hygiene. Eight appendices

contain very practical information on microbiological methods, formula-

tions of antimicrobial agents and treatment regimens.

The authors are all experts of international renown in the field of

ophthalmic infection and microbiology. The text is attractive, clearly laid-

out and beautifully illustrated with diagrams and coloured plates. Recom-

mended reading and references are also given.

This volume will become indispensable reading for those dealing with

eye infections as it presents essential information on patient management in

both temperate and tropical areas. It is a ‘must’ not only for ophthalmolo-

gists but also microbiologists, infectious disease physicians, pharmacists,

ophthalmic nursing staff and all medical and nursing libraries. At £35.00 it

is a bargain. Perhaps a handy, cheaper paperback version would improve

availability for developing countries.

E D Wright PhD FRCPath

Book Review


Ian Murdoch

MSc MD FRCOpth

Consultant Ophthalmologist

Moorfields Eye Hospital

City Road

London EC1V 2PD, UK

In ophthalmic research we have a prob-

lem. The collection of data for a project

usually involves examining and record-

ing observations on eyes. People generally

have two eyes and we often examine both.

The problem then comes in the analysis.

• Do we include all our data and talk abouteyes?

• Do we look at individuals?

• How should we deal with our data?

• Does it really matter?

Yes, it does matter!

There are a variety of ways people

analyse their data. The method employed

should depend on the question being asked,

the data-collected and the nature of the

condition being studied.

The Question Being Asked

Is the question relating to events or obser-

vations purely at an ocular level? For

example, trauma or the effect of corneal

opacity on the ability to diagnose cataract.

Does the question also include events or

observations which relate to the individ-

ual? For example, diet, systemic disease

(diabetes, hypertension, malaria) or social

factors. These examples are obvious. A

less obvious example of something that

relates to the individual is the response of

an optic disc to a given level of intraocular

pressure. This may be affected by the con-

nective tissue make-up and vascular sys-

tem, both of which relate to individuals.

If the question is purely at an ocular

level then there is no problem. Analyse

your data using eyes.

If the question includes events or obser-

vations which relate to the individual then

the method of analysis depends on the

nature of the condition being studied.

The Data Collected

If information on only one eye per person

has been collected then there is no prob-

lem; analyse your data using the eyes

(which also represent individuals). If infor-

mation on both eyes has been collected on

everyone in the study, then you need to

consider the nature of the condition being

studied before analysis.

There is a big potential problem when it

comes to data where information on one

eye has been collected on some people and

information on both eyes in other people. It

is generally safer to analyse only the data

of one eye per person in this situation.

The Nature of the Condition Being

Studied

Some cases are obvious. If your study con-

cerns visual disability then clearly the

results from both eyes are needed to show

how disabled the individual is and you

analyse your data at the level of the indi-

vidual. The same is true for squint.

The condition you are studying may

hardly ever affect both eyes in an indivi-

dual. An example of this is choroidal

melanoma which occurs in only one eye in

99% of cases.Other examples are corneal

herpes simplex infection in the immuno-

competent, or severe ocular trauma (98%

of cases). In these cases it is appropriate to

analyse at the level of the individual.

At the other extreme are conditions such

as blepharitis which almost always affects

both eyes (proportion bilateral 95%). This

means that whatever you find in the right

eye is almost bound to be exactly the same

as in the left eye (perfect correlation). The

result of this is firstly that there is no point

collecting data on both eyes. Why not save

effort and just use one eye per individual?

Certainly that is the way you should

analyse your data!

The majority of ocular conditions lie

between these two extremes.

If you know the intraocular pressure in

the right eye of patient A then you can

make an educated guess at the intraocular

pressure in the left eye of patient A. You

may not be correct because the IOP is not

perfectly correlated between eyes but you

have a reasonable chance of being correct.

There is more chance of being correct than

if you take the IOP in patient A’s right eye

and try to predict the IOP in the left eye of

patient B!

Routine statistical analyses rely on all

data points being independent of each

other. This means that you cannot predict a

second data point from the knowledge of

the first data point. From the above this

does not hold for IOP. Patient A’s right eye

and patient B’s left eye are independent.

Patient A’s right eye and patient A’s left

eye are not independent.

Clearly a simple answer is to use the

data of only one eye per person. This is

sound and safe statistically but in many

instances leads to a waste of data which

may be important. The analysis of data is

often aimed at estimates of effect or

descriptions of distributions. These are

expressed as figures with confidence inter-

vals. The ideal would be to include the

whole population and then the estimate

will not be an estimate, it will be the real

figure. Studies are done, however, on

samples of populations. The bigger the

sample the more accurate (precise) the esti-

mate of effect and the tighter (smaller) the

confidence intervals.

Forty eyes represent a bigger sample

size than 20 people! To use only 20 eyes in

the analysis is a waste. To use 40 eyes may

give a falsely high degree of precision.

Special techniques exist to make use of

all the data that has been collected in these

instances. These techniques, in this

example, make the sample size between 20

and 40. The more correlated the results are

between right and left eyes, the nearer the

sample size gets to 20. The less correlated

the results are between right and left eyes,

the nearer the sample size gets to 40.

We recommend discussion with a statis-

tician to help in both research planning and

analysis of data.


People and Eyes: Statistics in Ophthalmology

Indian Supplement to the Journal

The most recent issue has the following articles:

Management of Ocular Morbidity Following Injuries in an Agricultural Environment

Dr Philip A Thomas, Dr C A Nelson Jesudasan

Ocular Trauma in Tamil Nadu

Dr M Srinivasan

Printouts of these articles are available from

DANPCB, A1/148 Safdarjung Enclave, New Delhi 110029, India.

Fax: 91 11 618 1099.

Epidemiology


R B Porter BSc (Econ)Executive Director

Sight Savers International

Grosvenor Hall

Bolnore Road

Haywards Heath

West Sussex RH16 4BX, UK

In his introductory article in this Journal

(Vol. 11, Issue No. 25) on the Global

Initiative for the Elimination of Avoidable

Blindness, Björn Thylefors, Director of the

WHO Programme for the Prevention of

Blindness and Deafness, drew attention to

the huge burden imposed by blindness,

particularly in developing countries. Not

only are the numbers of blind and visually

disabled increasing, their number could

actually double by the year 2020 unless

urgent action is taken. And the tragedy is

that most of this is unnecessary – 80% of

blindness is either preventable or curable.

Efficient, effective and well-proven inter-

ventions are available to reduce dramati-

cally this increasing threat. Equally impor-

tant, although probably not so well known,

is the fact that these interventions include

some of the most cost effective available in

the whole of the health sector. This needs

to be given much greater emphasis if eye

care services are to compete successfully

for their fair share of health service budget.

The Economic Case

So what exactly is the economic case

for investing in blindness prevention

measures? Economic analysis in health

projects is ultimately concerned with com-

paring the costs with the related benefits.

Ideally this is done within the framework

of formal cost benefit analysis whereby

the costs and benefits associated with the

project over time are identified, quantified

and discounted.

This type of approach was adopted by

the World Bank in assessing the economic

impact of the African Programme for

Onchocerciasis Control.1 The Programme,

which will eliminate onchocerciasis (river

blindness) as a public health hazard in

Africa, was shown to deliver an economic

rate of return of 17%. This is an excellent

return by any standards and is all the more

impressive in that the study only took

account of the reduction in onchocerciasis-

related blindness and the associated

increase of the productive labour force as

the principal economic benefit. No account

was taken of oncho-related skin morbidity,

which other studies2 have shown to impose

a substantial burden on those infected and

on society in general. Inclusion of these

impacts would have demonstrated even

higher economic benefits.

One of the limitations of using full cost

benefit analysis in assessing health sector

programmes is the difficulty in quantifying

all associated costs and benefits. Some of

the benefits of blindness prevention and

cure can be reasonably measured, such as

savings in medical care costs, rehabilita-

tion and education costs and production

gains from return to work. What is more

problematic is quantifying and valuing

the less easily defined benefits such as im-

provement in well-being. For this reason,

another approach known as cost utility

analysis is often used to assess the com-

parative impact of health interventions.

Disability Adjusted Life Years

This approach was promoted in the 1993

World Bank Development Report, Invest-

ing in Health,3 and is based on a single

measure of health status known as Dis-

ability Adjusted Life Years (DALYs). It is

a combined indicator of the time lived with

a disability and time lost due to premature

mortality. It involves assigning weights to

different health states and multiplying

these by the number of years during which

that state persists – it is thus both a qualita-

tive and quantitative measure. When this

measure is considered with the availability

and costs of interventions, it leads to an

assessment of their comparative cost-

effectiveness, i.e., cost per DALY saved.

When applied to the leading causes of

blindness this yields some extremely

encouraging results. The cost utility of

more than 50 specific health interventions

were examined as part of World Bank

research.4 This showed cataract surgery to

be one of the most cost-effective of all

public health interventions. The cost per

DALY saved ranged from US$15 to just

over US$30, placing it in one of the lowest

bands. More recent evidence from the

Lumbini comprehensive blindness pro-

gramme in Nepal dramatically confirms

this, where the cost per DALY saved was

only US$5.5 This is an exceptional

example of the cost-effectiveness of

cataract interventions, and clearly local

conditions will determine the precise cost

of DALYs saved. Although it is a disease

of advancing age in the majority of cases,

its cost-effectiveness derives from charac-

teristics such as speed of operation, the

potential for high volume cataract surgery

and the high success rate.

But it is not only the treatments of

onchocerciasis and cataracts which are so

clearly worthwhile in economic terms.

Various studies6 into the cost-effectiveness

of interventions to reduce xerophthalmia, a

major cause of childhood blindness, show

comparable impacts. Thus, interventions

based on measles immunisation, fortifica-

tion of monosodium glutamate (MSG)

with vitamin A and mass dosage with

vitamin A capsules achieve costs per Daly

saved in the range of US$2–US$29.

There is less available evidence on

the cost- effectiveness/utility of traditional

interventions for the treatment of trachoma,

the leading cause of preventable blindness.

However, one very detailed study7 of

the trachoma control programme in

Myanmar using handicap-adjusted life

years (HALYs) as the composite measure,

rather than DALYs, demonstrated savings

of US$3 to US$11 per HALY, based on

marginal cost utility for non-surgical and

surgical interventions respectively.

Conclusion

All this evidence shows that outstanding

returns are available from interventions in

the key eye disease areas that have been

identified as priorities for action in the

Global Initiative. Not only are effective


The Global Initiative

GLOBAL INITIATIVEThe Economic Case

Table 1: Cost Benefit/Cost Utility of Eye Care Interventions

Eye Disease Cost per DALY saved (US$)

Cataract 5–32Childhood blindness (xerophthalmia) – Measles immunizaton 2–15– Vitamin A capsules (mass doses) 9– Fortification 29Trachoma 3–11 (HALY)Onchocerciasis 17% (Economic Rate of Return)


interventions available but they demon-

strate tremendous cost benefit/cost utility

when compared to other well-accepted

health interventions.

It is vital that the economic case support-

ing the Global Initiative is widely dissemi-

nated to maximise resource mobilisation

and ensure that blindness prevention pro-

grammes receive the priority they deserve

in international health programmes.

References

I Benton B. Economic impact of onchocerciasis

control through APOC: An over-view. World

Bank, 1997.

2 WHO. Economic impact of onchocercal skin

disease (OSD): Report of a multi-country study.

WHO 1997.

3 World Bank. Investing in health. World develop-

ment report 1993 and world development indica-

tors. World Bank, 1993.

4 Jamison DT et al, eds. Disease control priorities

in developing countries. Oxford University Press

for the World Bank, 1993.

5 Marseille E. Cost-effectiveness of cataract

surgery in a public health eye care programme in

Nepal. Bull WHO 1996; 74: 319– 24.

6 Levin H M et al. Micronutrient deficiency dis-

orders. In: Disease control priorities in develop-

ing countries, see 4 above, chapter 19.

7 Evans T G et al. Cost-effectiveness and cost

utility of preventing trachomatous visual impair-

ment: lessons from 30 years of trachoma control

in Burma. Br J Ophthalmol 1996; 80: 880– 9.


The Global Initiative

THE ROYAL COLLEGE OF OPHTHALMOLOGISTS

DIPLOMA IN OPHTHALMOLOGY EXAMINATION

The Royal College of Ophthalmologists has introduced an examination leading to the

award of the Diploma in Ophthalmology (DRCOphth). The examination will be held

twice a year, in June and November.

This Diploma is aimed at those not wishing to pursue a career as a consultant ophthal-

mologist in the United Kingdom. It should, therefore, be of interest to all doctors with

an interest in ophthalmology working outside the European Union.

Details are available from the Examinations Office, The Royal College of

Ophthalmologists, 17 Cornwall Terrace, London NW1 4QW.

Matthew D Wensor

Cathy A McCarty

Yury L Stanislavsky

Patricia M Livingston

Hugh R Taylor

Purpose: The purpose of the study was to

determine the prevalence of glaucoma in

Melbourne, Australia.

Methods: All subjects were participants in

the Melbourne Visual Impairment Project

(Melbourne VIP), a population-based

prevalence study of eye disease that includ-

ed residential and nursing home popula-

tions. Each participant underwent a stan-

dardised eye examination, which included

a Humphrey visual field test, tonometry,

fundus examination including fundal pho-

tographs, and a medical history interview.

Glaucoma status was determined by a

masked assessment and consensus adjudi-

cation of visual fields, optic disc pho-

tographs, intraocular pressure and glauco-

ma history.

Results: A total of 3271 persons (83%

response rate) participated in the residen-

tial Melbourne VIP. The overall preva-

lence rate of definite primary open-angle

glaucoma in the residential population was

1.7% (95% confidence limits = 1.21, 2.21).

Of these, 50% had not been diagnosed pre-

viously. Only two persons (0.1%) had pri-

mary angle-closure glaucoma and six per-

sons (0.2%) had secondary glaucoma. The

prevalence of glaucoma increased steadily

with age from 0.1% at ages 40 to 49 years

to 9.7% in persons aged 80 to 89 years.

There was no relationship with gender. The

authors examined 403 (90.2% response

rate) nursing home residents. The age stan-

dardised rate for this component was

2.36% (95% confidence limits = 0, 4.88).

Conclusions: The rate of glaucoma in

Melbourne rises significantly with age.

With only half of patients being diagnosed,

glaucoma is a major eye health problem

and will become increasingly important as

the population ages.

Published courtesy of:

Ophthalmology 1998; 105: 733-9

✩ ✩ ✩

Benefits and Costs of

Preventing, Treating and

Controlling Blindness:

A Preliminary Review and

Annotated Bibliography

by Health Economist

(WHO/ICEH)

Margaret Thomas.Available via e-mail only from

International Centre for

Eye Health at

[email protected]

Readership Survey – Prize Draw Winner

Congratulations to our winner,

Nurse C A Puka, Tanzania.

Our thanks to all who responded

to the questionnaire.

Abstract

The Prevalence of Glaucoma in the MelbourneVisual Impairment Project



Intraocular Lenses

High Quality Low CostIntraocular Lenses (IOLs)

FRED HOLLOWS

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IOLs manufactured in compliance with

EN46002 standards. EN46002 certification

pending for Kathmandu Fred Hollows IOL

Laboratory following recent audit and

recommendation by SGS Australia.

Available in 17 to 25 dioptre range in 0.5

dioptre increments. A Constant of 118.3.

Available from:

E r i t r e a: The Fred Hollows IOL

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Fax: 291 1 122532

email: [email protected]

N e p a l: The Fred Hollows IOL

Laboratory, Tilganga Eye Centre, PO Box

561, Kathmandu, Nepal.

Fax: 977 1 474937;


A u s t r a l i a: The Fred Hollows Foundation,

Locked Bag 100, Rosebery

NSW, 2018 Australia.

Fax: 61 2 9669 5188.


A U R O L A B

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(PC) and single piece posterior as well as

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factured in compliance with international

quality standards. Facility is ISO 9001

certified by Underwriters Laboratories

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Available in 5 to 30 dioptre range.

Special lenses available on request

include scleral fixation, low power and

custom designed types .

Available from:

India: A u r o l a b

Aravind Eye Hospital

1 Anna Nagar

Madurai 625 020, India

Fax: + 91 452 535274


www: http://aurolab.com

High quality, low cost IOLs are

available from the following

m a n u f a c t u r e r s :

Community Eye Health Courses 1998/9✦ MSc in Community Eye Health – 1 year (Sept. 99 – Sept. 2000)

✦ Diploma in Community Eye Health – 6 months (Sept.99 – Mar. 2000)

✦ Certificate Course in Community Eye Health – 3 months (Sept. – Dec.99)

✦ Certificate Course in Planning for Eye Care – 3 months (Jan. – Mar. 99)

✦ Short courses – 1–3 weeks (on-going)

Enquiries: Courses Promotions Officer, International Centre for Eye Health,

11–43 Bath Street, LONDON, EC1V 9EL, United Kingdom.

Fax: +44 171 608 6950; e-mail:[email protected]

T h e Journal of Community Eye Health is published four times a year.

Free to Developing Country Applicants

1999/2000 Subscription Rates for Applicants Elsewhere

1 Year: UK£25 / US$40 2 Years: UK£45 / US$70

(4 Issues) (8 Issues)

For more information, please contact: Journal of Community Eye Health,

International Centre for Eye Health, Institute of Ophthalmology,

11- 43 Bath Street, LONDON, EC1V 9EL, UK

Tel: (44) 171 608 6910 Fax: (44) 171 250 3207

e-mail: [email protected]

EEyyee HHeeaalltthh

Practical Paediatric

Ophthalmology

D Taylor and C Hoyt

Published 1997 by Blackwell Science Ltd

Osney Mead, Oxford OX2 0EL, UK

£39.50

David Taylor and Creig Hoyt have pro-

duced an excellent, compact book in 232

pages. There are many superb colour

photographs and illustrations. The text

itself is ordered and practical with liberal

use of bullet points together with boxed

information lists such as ‘The red eye in

infancy’, ‘Differential diagnosis of leuco-

coria’ and ‘Eye abnormalities and deaf-

ness’.

There are no references – to keep the

book a handy size. (The much larger

referenced text is David Taylor’s

Paediatric Ophthalmology, 2nd edition,

Blackwell Science 1997).

From the viewpoint of ophthalmology

in developing countries, readers of the

Journal of Community Eye Health will

need more in depth information regarding

vitamin A deficiency and the eye than

given here (perhaps in a future edition?).

Strabismus is dealt with in more detail

in the ‘twin’ book Practical Strabismus

Management by Vivian & Morris,

Blackwell Science 1997.

Paediatric eye problems such as geneti-

cally inherited disorders, infectious dis-

eases, cataract, glaucoma, trachoma,

tumours, neurological abnormalities, etc.,

are comprehensively, but concisely

covered.

Designed for general ophthalmologists,

paediatricians and those health workers

routinely faced with eye problems in child-

hood, I would have appreciated having

this book in my library many years ago,

especially when teaching in a developing

country.

D D Murray McGavin

MD FRCS (Ed) FRCOphth DCH

Book Review



Country Index

COMMUNITY EYE HEALTH

COUNTRY INDEXISSUES 1 – 24

Compiled by Sue Stevens

An index of countries and subjects covered in Issues 1-24 is beingpublished to mark the 10th anniversary of the Journal. For reasonsof space, the country index is published first. The larger, subjectindex will appear in the next issue.

KEY TO INDEX

A ABSTRACT / RESEARCH

L LETTERS

N REPORTS / NEWS

S SURGICAL ARTICLE

In 1993, volume numbers were introduced with Issue 11 (first issue of Vol.6).

Afghanistan N 10 23 44A 10 23 46N 2 10N 5 8N 6 10N 7 11

Australia A 10 24 62Bosnia A 10 23 46Botswana N 8 15 10

L 7 13 12Brazil N 8 16 26Cambodia N 10 23 37

A 10 23 46Cameroon N 6 12 30Egypt A 9 7Ethiopia N 10 23 40

N 7 13 9A 1 8

France A 7 7Gambia N 5 11Ghana L 8 16 28

A 7 7N 7 9

Grenada N 3 12India A 10 22 30

N 9 20 56N 6 12 22A 1 8N 1 10A 4 8N 4 9N 4 12A 6 6N 6 8N 10 10A 10 12N 6 11 9N 6 11 11N 6 11 12

Ireland A 4 7A 9 7

Israel A 7 6N 10 14

Jamaica N 8 16 30A 4 8

COUNTRY KEY VOL. ISSUE PAGE

Kenya A 1 9A 1 11A 4 8A 5 7

Liberia A 6 6A 9 8

Madagascar N 9 17 14Malawi A 1 12

A 2 9Mongolia A 10 22 30Mozambique A 10 23 46Nepal N 10 21 4

L 8 15 15N 6 12 19A 2 7N 3 9A 9 8A 10 12A 6 11 7

Netherlands A 4 11Niger S 9 18 28Nigeria S 10 21 6

N 10 21 14L 9 20 64A 7 6

Norway A 6 11 6Oman A 10 13Pakistan N 10 24 57

A 1 8A 2 9N 2 10N 4 10N 6 11 15

Paraguay N 10 22 24Peru A 1 12Rwanda N 8 15 13

A 2 8Saudi Arabia A 1 9Senegal S 10 21 10Sierra Leone A 10 22 31

L 7 13 16A 10 13A 4 7

South Africa A 9 18 32N 2 7A 4 6

Sudan A 7 13 12N 6 11 7

Tanzania L 9 20 62A 1 8A 5 7A 5 9A 9 7A 10 13A 6 11 6

Thailand A 4 11Togo N 10 22 32Turkey N 7 13 2Uganda N 8 10

N 10 8USA A 7 13 12

A 5 6Zimbabwe N 10 21 3

L 6 12 32A 3 10N 3 11N 9 9N 10 6



Tenth Anniversary

The Journal of Community Eye Health

is 10 years old! After working in a

developing country, my vision was for a

Journal which would bring health workers

relevant, up-to-date information on oph-

thalmic clinical practice, research, personal

successes and learning experiences, as well

as views and comments. Funding was

secured by Professor Gordon Johnson,

Director, International Centre for Eye

Health from Christoffel Blindenmission

and Sight Savers International. Today, both

organisations continue their generous sup-

port to the International Resource Centre.

During the last 10 years there has been

encouraging support from a variety

of organisations, including HelpAge

International, The Coca-Cola Company,

The Stanley Thomas Johnson Foundation,

The Ulverscroft Foundation, The Inter-

national Glaucoma Association and the

Department for International Development

(UK). We thank them, and the many spon-

sors of individual issues whose support

towards publication costs is vital to the

Journal’s success.

The circulation is 15,000 to 160

countries, and rising. In 1994, in co-

operation with colleagues in India, and

supported by the Danish Assistance to the

National Programme for Control of

Blindness (DANPCB), an Indian edition

was published with a 4-page supplement.

This has been a success, with our circu-

lation rising in India alone from 2,000 to

over 7,000! We pay tribute to our

colleagues in India and express real grati-

tude to DANPCB for their support.

We have experienced many encourage-

ments, and, very occasionally, some

difficulties! One concern for the Editor

is that accumulated articles are waiting

for review and possible publication. My

apologies to those who have sent articles to

us and are awaiting the outcome.

Since we began our thematic approach we

have had less space for many good papers.

But we still want to receive contributions!

We list below the themes that will be

covered in 1999 and invite you to send us

short reports (5–600 words), comments

and letters on relevant topics that con-

tribute to improving practice (publication

guidelines are available on request).

Journal Survey

In recent months a review of the Journal

has been carried out by an independent

consultant. Our thanks to the many readers

who responded to the questionnaire. The

responses tell us that a single issue of the

Journal is shared, on average, by 5–8

people. Over 90% of you have a teaching

role and for 40%, teaching is a ‘major’ part

of your work. More than 90% endorse our

theme approach and 60% have advised

us of ways in which the Journal has

influenced or changed their practice.

Significantly, 60% have no access to other

literature to keep them informed of current

practice and opinion.

While many who read the Journal are

ophthalmologists (30%), we are encour-

aged that 70% are in allied professions

involved in eye care services. Our aim is

to reach a broad spectrum of health

workers, and the survey’s breakdown

of colleagues receiving the Journal incl-

udes doctors (19%), ophthalmic nurses

(12%), general nurses (9%), ophthalmic

assistants (8%), medical assistants (7%),

optometrists/refractionists (5%), commu-

nity health care workers (4%) and others,

such as administrators and librarians (6%).

We do want individual health workers

to have their own copy. To receive your

own copy or to add a colleague’s name to

our mailing list, please send us a note of

your name, occupation and address.

Future Plans

Your feedback has helped us to plan for

1999 and beyond, as follows:

• Continue to publish 4 issues of the

Journal each year. In 1999 the four topics

will be:

– Ageing and the Eye

– The Red Eye; Conjunctivitis and

Corneal Ulcer

– Community Participation

– Assessment of Vision

• Begin a pull-out section on Teaching

Eye Health in mid-1999

• Increase the number of colour pages

from the present 4 to 8 in 1999 and then

to 12 in 2001

• Increase efforts to make the Journal

available in regional and translated

editions

• Publish a Global Prevention of Blindness

Review of selected Journal articles in

English in 1999 and in other languages in

future years.

The team at the International Resource

Centre (see photos) is supported in its work

by the Editorial Review Committee (see

page 34) which meets quarterly, our team

of Consulting Editors and Language &

Communication Consultant (also see page

34), and an Editorial Planning Committee

which meets annually. Many others have

contributed during the evolving years of

the Journal. These include Dr John D C

Anderson, Ms Keren Fisher, Mr Pak Sang

Lee, Mrs Sybil Lee, Dr Hans Limburg, Mr

Hugh Lugg, Dr Sajabi Masinde, Professor

Erasmus Oji, Dr Roger Sidestam, Ms Sarah

Stubbs and Ms Faith Wakeford.

As Editor, during these years, I express

my deep appreciation to these colleagues

and friends, and to all who have written for

us, whether their articles, comments and

letters have been published or have yet to

be included. Each one has contributed to

the effective impact of this publication

which, we believe, has a unique role in the

prevention of blindness and community

eye health.

D D Murray McGavin

Editor

Murray McGavin Photo: Ruth McGavin

Journal of Community Eye Health

10th Anniversary: 1988–1998

Anita Shah & Ann NaughtonPhoto: Sue Stevens

Sue StevensPhoto: Murray McGavin


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